Taximeter having device for electronically setting increased base fare rate

ABSTRACT

A taximeter having no speed governor and provided with a device for electronically setting an increased base fare rate, comprising an electronic oscillation circuit for generating a train of pulses for driving a taximeter drive motor, and means for varying the time constant of the oscillation circuit thereby counting the fare at a selected increased base fare rate.

[111 3,873,811 5] Mar. 25, 1975 United States Patent [191 Ozaki et al.

References Cited UNITED STATES PATENTS TAXIMETER HAVING DEVICE FORELECTRONICALLY SETTING INCREASED BASE FARE RATE 235/30 R 58/23 ACKelch.........l....i.....

Nilsson.........i.....:.l Spauszus et al.......

n 6 6 6 B K 62334 67 77 7 9 9 999 HUN 5 04 65228 900682 l i v 93004340060 27778 [75] Inventors: Noboru Ozaki; Masatoshi Shimizu,

both of Shimada, Japan [73] Assignee: Yazaki Sogyo Kabushiki Kaisha,

Tokyo, Japan [22] Filed Nov 14 1973 Primary Examiner-Stephen J. TomskyAttorney, Agent, or FirmOldham & Oldham Co.

[21] Appl. No.: 415,680

ABSTRACT A taximeter having no speed governor and provided [30] ForeignApplication Priority Data Dec. 1, 1972 with a device for electronicallysetting an increased base fare rate, comprising an electronicoscillation circuit for generating a train of pulses for driving ataximeter drive motor, and means for varying the time constant of theoscillation circuit thereby counting the fare at a selected increasedbase fare rate.

0 6 RH 7 w M B 3 278 U 0 U u 9 n T 7 .m2H u 9 1 n H ,3 u MR 3 H m0 .e mm .l I w UhF HUM 55 5 1 Claim, 5 Drawing Figures l TAXIMETER HAVINGDEVICE FOR ELECTRONICALLY SETTING INCREASED BASE FARE RATE Thisinvention relates to a taximeter having an increased base fare ratesetting device which is simple in construction and can operate reliably.

Prior art taximeters employ a clock mechanism which consists essentiallyof a power source means such as a hand-actuated power spring, a solenoidor a drive motor, a speed governor and a train of geared wheels. Theinherent complexity of this clock mechanism has been disadvantageous inrespect of production costs and has resulted in an increased tendencytoward possibility of mal-operation and trouble. Further, sometaximeters are designed for counting the fare on the basis ofapredetermined time and various increased base fare rates are approved insome districts. Therefore, in the districts in which these variousincreased base fare rates are approved, the prior art clock mechanismadapted for merely counting the increased base fare on the basis of thepredetermined time is not suitable for the purpose and some means forcounting, for example, a 20 percent increased base fare and a 30 percentincreased base fare must be added to the taximeter. However, the clockmechanism has the inherent property of punctuality due to the fact thatthe speed governor is employed therein. Therefore, means for settingthese increased base fare rates must be disposed in the stage after thestage including the speed governor, However, provision of such meansconsisting of mechanical parts adds another complexity to the taximeterand is difficult in view of the limited space available for thetaximeter presently widely used.

With a view to obviate such difficulties, it is a primary object of thepresent invention to provide a novel taximeter in which the speedgovernor is eliminated, an electronic oscillation circuit is providedfor controlling the drive motor in the clock mechanism by clock pulseswith exact timing, and the time constant ofthis oscillation circuit issuitably varied to vary the frequency of the clock pulses therebycarrying out the counting of the fare on the basis of the selectedincreased base fare rate.

The above and other objects, features and advantages of the presentinvention will be apparent from the following detailed description of apreferred embodiment thereof taken in conjunction with the accompanyingdrawings, in which:

FIG. I is a wiring diagram of an electronic circuit in a taximeteraccording the present invention;

FIG. 2 is a diagrammatic view showing the arrangement of a gear trainfor transmitting power from a drive motor to a clutch means;

FIG. 3 is a schematic perspective view showing the arrangement of thedrive motor, gear train, clutch means and fare display drum;

FIG. 4 is a schematic perspective view of part of the taximeter whenviewed from the side opposite to that shown in FIG. 3; and

FIG. is a schematic sectional view showing the driving connectionbetween a drum advancing ratchet wheel and the fare display drum.

A taximeter according to the present invention includes a clockmechanism which comprises a pulse generator as shown in FIG. 1, a geartrain as shown in FIGS. 2 and 3, a clutch means as shown in FIGS. 3 and4, and fare counting means as shown in FIGS. 3 to 5.

The electrical circuit shown in FIG. 1 is printed on a printed circuitboard and is divided into a plurality of sections A to F surrounded bythe dotted lines. The section A is a constant-voltage power supply meanswhich is composed of a stabilizing resistor Rs and a Zener diode ZD andregulates the variable voltage of the power supply in the vehicle to aconstant voltage for supplying this constant voltage to the section B.The section B is an astable multivibrator which is composed oftransistors T T capacitors C C C C resistors R,, R R R and semi-fixedresistors VR VR VR for generating a train of clock pulses. An externallyactuated changeover contact 10 is provided in the section B forselectively connecting one of the variable resistors VR,, VR and VR inseries with the resistor R The time constant determined by this resistorR selected variable resistor and capacitor C determines the oscillationfrequency of the astable multivibrator. Therefore, the'base fare ratesuch as the non-increased base fare rate, 20 percent increased base farerate or 30 percent base fare rate can be set as desired by selecting oneof these semi-fixed resistors and varying the frequency of the clockpulses.

The rectangular waveform collector output of the transistor T g in thisastable multivibrator is applied to the section C. The section Cincludes a differentiator which is composed of a capacitor C and aresistor R for differentiating the rectangular waveform collector outputof the transistor T The output of the differentiator is applied to thesection D through a steering circuit which is composed of diodes D D andD The section D is a bistable multivibrator which is composed oftransistors T T capacitors C C C C and resistors R R R R In response tothe application of the differentiated input to the base of thetransistor T and T from the steering circuit in the section C, thesection D delivers an output having a waveform such that the frequencyof the output of the section B is divided into [2. The section D isprovided for obtaining a waveform having a 0" level and a "1 level ofequal duration due to the fact that the 0 level and l level in theoutput waveform of the section B are not equal to each other and thisoutput waveform is not suitable for causing rotation of a drive motor16.

The section E is a motor driving circuit which acts to amplify theoutput of the section D (appearing at the collector of the transistorsT,;, and T,.,) by transistors T to T for driving the motor 16. Diodes Dand D are provided for preventing application of a surge voltage.

The section F includes the winding M of the motor 16. The motor 16 isrotated by alternately flowing current through the portions on oppositesides of the central point, and the number of revolutions of the motor16 is proportional to the frequency of the current supplied to thewinding M. This motor 16 is of the type which is commonly called abifilar timing motor in the art. The drive motor 16 having a structureas above decribed rotates at one of a plurality of speeds depending onthe position of the externally actuated changeover contact 10 in theoscillator mounted in the taximeter. For example, the motor 16 rotatesat a speed of 250 rpm. to count the fare at a rate of 30 yen every 3minutes when the base fare is set at the ordinary base fare rate, andthe rotating speed of the motor 16 is increased to 300 rpm. so as tocount the fare according to a 20 percent increase base fare rate whensuch rate is set by thechange-over of the contact 10.

The rotation of this drive motor 16 is reduced by a train of gears Z toZ which are supported together with the motor 16 on a mounting plate 12fixed to another mounting plate 13 as shown in FIGS. 2 and 3, and theincreased torque is transmitted to a clutch means 15. This clutch means15 is selectively actuated depending on the running condition of thetaxi sothat the fare can be counted on the basis of the distance run bythe taxi or on the basis of the time lapsed during running. Taximeterspresently widely employed are designed to count the fare onthe basis ofthe time when the running speed of the taxi is reduced to less than Km/hin the district in which the fare is counted on the basis of both thedistance and the time. The rotation of the clutch means causes rotationof a cam 19 in a direction shown by the arrow in FIG. 4 for counting thefare. A drum advancing lever 17 having a pawl 23 at one end thereof ispivoted at the other end thereof to a mounting plate 11 as shown in FIG.4. A counter lever spring 21 is anchored at one end thereof to the plate11 and at the other end thereof to a pin fixed to the lever 17 so as toensure rolling engagement between a roller 18 pivoted to the lever 17and the cam 19. Thus, the rotation of the cam 19 in the direction shownby the arrow in FIG. 4 causes vertical swinging movement of the lever 17in directions shown by the arrows. This vertical swinging movement ofthe lever 17 causes rotation of a ratchet wheel 22 in a direction shownby the arrow by the action of the pawl 23 engaging with the ratchetwheel 22. A gear 24 is mounted on the shaft of the ratchet wheel 22 forunitary rotation therewith and is in meshing engagement with a gear 25mounted on the shaft of a fare display drum 14 as shown in FlG. 5. Thus,the rotation of the ratchet wheel 22 causes rotation of the fare displaydrum 14 which counts the fare.

It will be understood from the foregoing detailed description that, inthe taximeter of the present invention having a structure as abovedescribed, mechanical means for setting the increased base fare rate areutterly unnecessary due to the fact that such increased base fare ratecan be set electronically. Further, the presentinvention is advantageousin that the speed governor is entirely unnecessary and a small-sizedassembly having a simple construction can attain the complex function ofsetting the increased base fare rate. Thus, the taximeter according tothe present invention can operate with very high precision andreliability.

What is claimed is:

1. A taximeter having fare indicating means and a device forelectronically controlling a time signal generating mechanism toestablish a base fare rate, comprising:

an astable multivibrator, including a plurality of variable resistorsselectively in connection with a capacitor through anoperator-actuatable switch;

a differentiator connected to the astable multivibrator, receiving anddifferentiating the output thereof;-

a bistable multivibrator connected to said differentiator and receivingthe output thereof and accordingly producing a symetrical square wave;

a motor for driving said fare indicating means; and

a motor driving circuit interconnected between the motor and thebistable multivibrator for driving said motor at a rate commensuratewith the frequency of the signal from the bistable multivibratOl'.

1. A taximeter having fare indicating means and a device forelectronically controlling a time signal generating mechanism toestablish a base fare rate, comprising: an astable multivibrator,including a plurality of variable resistors selectively in connectionwith a capacitor through an operator-actuatable switch; a differentiatorconnected to the astable multivibrator, receiving and differentiatingthe output thereof; a bistable multivibrator connected to saiddifferentiator and receiving the output thereof and accordinglyproducing a symetrical square wave; a motor for driving said fareindicating means; and a motor driving circuit interconnected between themotor and the bistable multivibrator for driving said motor at a ratecommensurate with the frequency of the signal from the bistablemultivibrator.